Quench Dynamics of Isolated Many-Body Quantum Systems

Understand

We study isolated quantum systems with two-body interactions after a quench.

• In these systems, the energy shell is a Gaussian of width $\sigma$, and it gives the maximum possible spreading of the energy distribution of the initial states.
• When the distribution achieves this shape, the fidelity decay can be Gaussian until saturation.
• This establishes a lower bound for the fidelity decay in realistic systems.